Hello,
I have a 2000 cherokee sport with the 4.0 eng. I have removed the old eng. that threw a rod. I am searching for a replacement and wondering about compatibility with other years/models. what will work with my 2000 chasis (auto trans; 4X4)???...thanks!

thoag

08-13-2012 10:49 PM

I be leave every motor 4.0 from 97 to 02 were the same but don't quote me

I've posted what changed and when with the 6-242 engine on several boards, and I think this was one of them - you may want to check.

You'll find your options will open up, however, if you look for a short block and clean up the head. Every 6-242 block will accept every 6-242 head, and even the 1975-up 6-258 uses the same screws and screw pattern as the 6-242 (earlier sixes use 7/16"-14 screws, which requires some small adaptation to make them work.)

If you use a RENIX block, just ignore the drilled/tapped hole for the knock sensor (or just put a screw in there and call it good - the hole doesn't communicate with any fluids.)

There were changes to the block (internally - casting revisions) ca. 1991, 1996, and 1999 - but that won't have anything to do with accepting a cylinder head. (Revisions were usually due to NVH - Noise, Vibration, Harshness - concerns.)

I have heard there were differences in mounting between the TJ/YJ and the XJ/MJ/ZJ/WJ, but I can't swear to anything. However, they're probably adaptable as well, I'm just not sure how much effort would be involved.

The 2000 XJ 6-242 should have the #0331 head - which was used 1999-up in the TJ and WJ, and 2000-2001 in the XJ. However, there earlier #0331 heads (through about mid-2001) hare the ones that crack, they've ogt about a 50/50 chance of doing it. The heads were revised ca. mid-2001, the revised head carries a cast-in "TUPY" mark on the upper surface.

Typically, the cracking occurs ~150-180Kmiles, and if they crack, it will be on the upper surface, roughly under the oil fill cap (between the #3 and #4 cylinders.) Any of the later #0331 heads will replace the earlier ones, so there are more heads that are less likely to crack than heads that are likely to do so (make sense? I wasn't sure how to phrase that.) Manifolds and attachments will readily swap.

HTH, YMMV

cruiser54

08-18-2012 10:10 PM

This may shed some light on the different blocks:
XJ Cherokee and ZJ Grand Cherokee 4.0L engine blocks interchange.

I'd thought there was something going on. Do you have any idea what the specific differences might be?

CJ7-Tim

08-21-2012 07:07 AM

TJ/WJ 4.0L Engine blocks underwent significant design changes effective in the 1999 WJ Grand Cherokee and 2000 TJ Wrangler. These blocks are not interchangeable with any XJ/ZJ engine blocks. The reason why is because motor mount bolt holes and belt driven accessory mounting bolt holes are in different locations, or not present at all, TJ/WJ vs. XJ/ZJ.

Some hole locations are not drilled/tapped, and some simply have no material on the block for a hole to be located in. The swap can be accomplished, but is not worth the efffort.

JazzGallons

04-16-2013 11:51 AM

Transmission

Is this the same for transmissions. I have a 1998 wrangler 4.0 and have a 1998 cherokee transmission that I was wanting to put in.

Simmbad

04-24-2013 11:21 PM

Sorry to jump on your tread, what would the best replacement motor be for a 1989 4.0.... I am in CA so it needs to pass smog... or just rebuild the one I have?

cruiser54

04-25-2013 06:20 AM

This will help you. Just use all your "external" stuff.

Cruiser’s HO into Renix Swap

This swap is easier than some will lead you to believe, generally those who have never done it. Those of us who have done it, like myself, will share with you the things that need to be done for a successful swap. Just think of it as swapping in a long block.

The HO and Renix have some differences but none that can’t be overcome very easily.

Any HO engine from an XJ or ZJ through 1999 can be used. One running change was that the rear of the head was no longer drilled and tapped for the temperature gauge sender beginning in the 96 model year. The sender can be relocated to the threaded hole in the thermostat housing taken from the HO engine. You’ll have to extend the wire to that location. Some brave souls even drill and tap the HO head for the sender.

You will be using the intake and exhaust manifolds from your Renix, along with all your sensors and wiring. Since the intake ports of the HO are slightly different, you use the Renix gasket. Exhaust ports are identical.
You will need to use your Renix distributor as it is different than the HO because they use different fuel management systems. The flywheel or flexplate from the Renix must be used so your CPS gets the correct signals. The valve cover from the Renix allows you to keep your CCV system intact and requires no modifications.

The HO block will have a plug in the coolant galley on the driver’s side of the block, closest to the front, which needs to be removed so your Coolant Temp Sensor can be installed in it’s place just as it is on the Renix. It requires a 5/16” square drive or a modified 3/8” drive that has been ground down to fit. Do this before installing the engine.

As for the knock sensor, which is located just above the oil pan on the driver’s side of the engine about mid way, all the blocks I’ve seen are threaded for it. If not, I’ve heard they may be drilled but not tapped. Tap the hole if that’s the case.

Revised 03/28/13

Simmbad

04-26-2013 07:23 PM

Thank for the info, have seen afew low mileage HO motors and had wondered if they would work. My current 4.0 has over 200k on it.

cruiser54

04-26-2013 09:16 PM

Quote:

Originally Posted by Simmbad
(Post 15353483)

Thank for the info, have seen afew low mileage HO motors and had wondered if they would work. My current 4.0 has over 200k on it.